Seleucus II Callinicus in Wikipedia
Seleucus II Callinicus or Pogon (Greek: Σέλευκος Β' Καλλίνικος , the epithets meaning "beautiful victor" and "bearded", respectively), was a ruler of the Hellenistic Seleucid Empire, who reigned from 246 to 225 BC. After the death of this father, Antiochus, he was proclaimed king by his mother, Laodice in Ephesos, while her partisans at Antioch murdered Berenice and her son.
This dynastic feud began the Third Syrian War. Ptolemy III, who was Berenice's brother and the ruler of Egypt, invaded the Seleucid Empire and marched victoriously to the Tigris or beyond. He received the submission of the Seleucid Empire's eastern provinces, while Egyptian fleets swept the coast of Asia Minor.
Seleucus managed to maintain himself in the interior of Asia Minor. When Ptolemy returned to Egypt, Seleucus recovered Northern Syria and the nearer provinces of Iran. However, Antiochus Hierax, a younger brother of Seleucus, was set up as a rival in Asia Minor against Seleucus by a party to which Laodice herself adhered.
At Ancyra (about 235 BC) Seleucus sustained a crushing defeat and left the country beyond the Taurus to his brother and the other powers of the peninsula. Seleucus then undertook an anabasis to regain Parthia, the results of which came to nothing. According to some sources, he was even taken prisoner for several years by the Parthian king. Other sources mention that he established a peace with Arsaces I, who recognized his sovereignty.
In Asia Minor, Pergamon now rose to greatness under Attalus I. Antiochus Hierax, after a failed attempt to seize his brother's dominions when his own were vanishing, perished as a fugitive in Thrace in 228 or 227 BC.
About a year later, Seleucus was killed by a fall from his horse. Seleucus II married his cousin Laodice II, by whom he had five children and among them were: Antiochis, Seleucus III Ceraunus and Antiochus III the Great. He was succeeded by his elder son, Seleucus III Ceraunus, and later by his younger son Antiochus III the Great.